Electric locomotive VL80T: worn traction gear drive restored without disassembly

State Enterprise "Kharkiv Certification Body for Railway Transport", Ministry of Transport of Ukraine · director: Dr. Sc. (Eng.), Prof. E. D. Tartakovsky · responsible executor: Cand. Sc. (Eng.) A. B. Babanin

Kharkiv, Ukraine · experiment 15.04–24.07.1998, Znamianka locomotive depot, Odesa Railway · report 1998

PRODUCTXADO RVS tribotechnical compound3 % in the standard sulphurized grease of the traction gear case

TEST OBJECTElectric locomotive VL80T-1433Traction gear drive: two treated gear pairs and one control pair on the same locomotive

DOCUMENT TYPEResearch and development report,
signatures and stamps

Key results

↓52.1pp

pinion tooth wear as share of the maximum allowable, 97.0 → 44.9 %

↑0.39-0.55mm

tooth thickness of the treated gear wheels, 12.27-12.33 → 12.72-12.82 mm

↓0.42mm

tooth thickness of the untreated gear wheel over the same mileage, 13.80 → 13.38 mm

OBJECT	CONDITION AT START OF TESTS	WHAT WAS MEASURED
Electric locomotive VL80T-1433, freight train haulage Znamianka – Piatykhatky and Znamianka – Myronivka	864,000 km since major overhaul, average daily run 400 km	Mileage during the experiment 33,988 km over 100 days
Gear pair of the 3rd wheelset, left — treated	Pinion wear 97.0 % of the maximum allowable	Tooth thickness at constant chord, wear as share of maximum allowable
Gear pair of the 5th wheelset, left — treated	Gear wheel tooth thickness 12.27 mm, pinion 14.67 mm	Tooth thickness at constant chord
Gear pair of the 5th wheelset, right — control	Gear wheel tooth thickness 13.80 mm, pinion 14.22 mm	Same mileage, standard grease, measurements on the same days

Tooth thickness at constant chord — treated pairs and the control pair

COMPONENT	AT START, mm	21,000 KM	34,000 KM	CHANGE
Pinion of the 3rd wheelset — treated	14.25	14.92	15.28	+1.03 mm
Gear wheel of the 3rd wheelset — treated	12.33	12.72	12.72	+0.39 mm
Pinion of the 5th wheelset — treated	14.67	14.72	14.80	+0.13 mm
Gear wheel of the 5th wheelset — treated	12.27	12.68	12.82	+0.55 mm
Pinion of the 5th wheelset, right — control	14.22	13.98	14.00	−0.22 mm
Gear wheel of the 5th wheelset, right — control	13.80	13.46	13.38	−0.42 mm

Reference gear tooth caliper, averaging over 3 centre-punched pinion teeth and 5 gear wheel teeth; measurements taken at scheduled maintenance and current repairs. The control pair ran on the standard grease of the same locomotive.

Tooth wear as share of the maximum allowable — 3rd wheelset

COMPONENT	NOMINAL	WEAR LIMIT	WEAR BEFORE	WEAR AFTER
Small pinion, 21 teeth	16.16 mm	14.20 mm	97.0 %	44.9 %
Large gear wheel, 88 teeth	14.58 mm	11.80 mm	82 %	66.9 %

The nominal value and the wear limit are the component's rated data as quoted in the report. At the start the pinion stood practically at the scrapping limit.

Conclusion of the certification body

The State Enterprise "Kharkiv Certification Body for Railway Transport" recorded the following upon completion of the experiment: "The aim of the experiment, partial restoration and hardening of the tooth surface with a metal-ceramic coating, has been achieved." The measurements showed that "on the experimental pinions and gear wheels the tooth thickness increases, while on the control ones wear continues." The pinion of the 3rd wheelset, which at the start stood practically at the scrapping limit, regained half of the allowable wear — without disassembling the unit and without withdrawing the locomotive from service. The report found the use of the technology on traction gearboxes expedient and recommended an extended experiment on metro rolling stock: 15 experimental and 15 control cars with an observation period of 12 months.

The results apply to the traction gear drive of VL80T mainline electric locomotives in freight service; with other components and duty cycles the figures may differ. RVS is an obsolete XADO designation for the zero-generation compounds; the current product generation is revitalizants. The original report with signatures and stamps is published in full and available for download.

Current equivalent

Revitalizant gel for gearboxes →

Industrial gearboxes, final and central drives, truck and tractor gearboxes, open gear and chain drives.

How such units are treated: Gear drive

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